Speaker-level inputs or line output converter (LOC)?
Solved: Nature of Audio Line Out connection? - HP Support Community - 6772643
Amazon.com: AudioControl LC2i PRO 2-Channel Line Output Converter with Impedance Matching, AccuBASS, GTO, Audio Signal Sense, 12V Turn-On and ACR-1 Dash Remote Subwoofer Control : Electronics
Audio Line In and Out
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Line Level Signals Explained | SWAMP
Audio Line In and Out
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